The present invention relates to an optical disk drive and medium for recording or reproducing information by applying a converged laser beam to information tracks concentrically or spirally formed on, for example, a discoid recording medium.
The recording methods of conventional optical disks in which data can be overwritten, as disclosed in Japanese Patent Laid-Open No. 46231/1989 and in U.S. Pat. No. 5,257,256, convert a recorded code train into pulses and rewrite, i.e. record new information while erasing old information.